GetSchema("DataTypes") does not return entries for JSON and VECTOR types

### Describe the bug

`SqlConnection.GetSchema("DataTypes")` does not include rows for the built-in SQL Server types **JSON** and **VECTOR**.

### To reproduce

```c#
using Microsoft.Data.SqlClient;

using var connection = new SqlConnection("Server=.;Database=master;Integrated Security=true;");
connection.Open();

var table = connection.GetSchema("DataTypes");

bool hasJson = table.Rows.Cast().Any(r => ((string)r["TypeName"]).Equals("json", StringComparison.OrdinalIgnoreCase));
bool hasVector = table.Rows.Cast().Any(r => ((string)r["TypeName"]).Equals("vector", StringComparison.OrdinalIgnoreCase));

Console.WriteLine($"JSON found: {hasJson}");
Console.WriteLine($"VECTOR found: {hasVector}");
```

**Actual**: both return `false`
**Expected**: both types should be included

### Further technical details
Microsoft.Data.SqlClient version: all versions, including prerelease
.NET target: all
SQL Server version: SQL Server 2025
Operating system: any